1. Field of the Invention
The present invention relates to modular insulating concrete forms of the type which receive poured concrete and are abandoned in place after pouring, thereby becoming an integral part of a static structure being built. The invention is particularly applicable to residential and light commercial construction. The novel forms are usable by homeowners, contractors, municipal, industrial, and institutional personnel in building and improving existing structures wherever insulated load bearing walls are to be built from poured concrete.
2. Description of the Prior Art
Left-in-place insulting concrete forms for building foundations and load bearing walls from poured concrete are known. In commercial practice, courses of forms are stacked until the final desired height of a wall is attained. Concrete is poured into the erected forms and allowed to cure. The resultant wall must provide both strength and also insulation protection against the elements. Insulating concrete forms have been proposed to answer these needs. In order to maximize both strength and insulation values within a given volume dedicated to a left-in-place form wall, the concrete elements must be carefully designed to utilize a minimum amount of concrete, so that the balance of the available volume may be filled with the insulating form.
One of the more common designs is the so-called “waffle grid” type. The waffle grid design takes its name from the visual impression of the internal surfaces of its constituent form walls. Intersecting posts and beams formed after pouring of concrete, which would otherwise leave openings, are complemented by webs which close these openings. The webs are considerably thinner than the posts and beams. The overall visual effect is similar to that of typical waffle irons. Waffle grid walls, as well as all insulating concrete form walls, must address several needs.
One is that it is necessary that each form be properly aligned with respect to adjacent forms to assure that finished wall surfaces are flat and flush. Also, opposing exterior panels of each form section must be held in place without distortion of overall configuration of the finished wall.
A second problem of prior art forms is that they are not designed such that locations of tie brackets coincide with the ends of standard building elements. Illustratively, sheets of plywood and gypsum wall board are typically provided with length of eight feet and height of four feet. If a form section has tie brackets and associated plates or flanges serving as a structural members which can receive driven and threaded fasteners, and these plates or flanges are located at each end of the form section, then abutment of two form sections results in abutting plates or flanges. This arrangement will likely interfere with even spacing apart of tie brackets at even distance intervals of a whole number of feet since the two abutting end brackets will be spaced on either side of the center line. Thus, if a fastener is driven at the point of abutment, there will be no solid structural member to receive the fastener.
This makes it difficult to properly locate fastener positions for attaching building elements to the form. Flange location can be calculated, but calculation entails additional effort when constructing forms.
Another problem is that the prior art has not provided insulating concrete form walls which are conducive to laying a wall in increments of one foot, as measured from the outside corner, as is frequent construction practice. Prior art forms typically require shortening by cutting to accommodate building walls laid out in increments of one foot.
A representative waffle grid design and a representative post and beam design are illustrated in a color brochure entitled “Insulating Concrete Forms: Comfort And Security In An Easy-To-Use Package” (undated), published by the Insulating Concrete Form Association, Glenview, Ill. 60025.
Another problem of existing waffle grid insulating concrete forms is that none known to the present inventor has means for interlocking with forms of courses above and below. The prior art fails to describe the instant invention as claimed.